Two sets of high-quality spectroscopic orbits for both components of ZZ UMa are available. Lacy & Sabby [1]} obtained 27 high-resolution spectra and measured RVs for both components in each. Imbert [2]} presented 33 RVs for star A, of which 28 were from Coravel [3]} and five from Élodie [4]}, and 16 RVs for star B, of which 12 were from Coravel and four from Élodie. The Coravel RVs have a greater scatter than those from Lacy & Sabby, whereas the Élodie RVs have a much lower scatter.
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